5.5

CVE-2026-21870

Exploit

The BACnet Protocol Stack library has an Off-by-one Stack-based Buffer Overflow in tokenizer_string

BACnet Protocol Stack library provides a BACnet application layer, network layer and media access (MAC) layer communications services. In 1.4.2, 1.5.0.rc2, and earlier, an off-by-one stack-based buffer overflow in the ubasic interpreter causes a crash (SIGABRT) when processing string literals longer than the buffer limit. The tokenizer_string function in src/bacnet/basic/program/ubasic/tokenizer.c incorrectly handles null termination for maximum-length strings. It writes a null byte to dest[40] when the buffer size is only 40 (indices 0-39), triggering a stack overflow.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
Bacnetstack ≫ Bacnet Stack Version <= 1.4.2
Bacnetstack ≫ Bacnet Stack Version1.5.0 Updaterc1
Bacnetstack ≫ Bacnet Stack Version1.5.0 Updaterc2
Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.24% 0.149
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
security-advisories@github.com 5.5 1.8 3.6
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CWE-193 Off-by-one Error

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-pc83-wp6w-93mx
Vendor Advisory
Exploit
https://github.com/bacnet-stack/bacnet-stack/pull/1196
Patch
https://github.com/bacnet-stack/bacnet-stack/commit/4e1176394a5ae50d2fd0b5790d9bff806dc08465
Patch